From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Wunderlich Subject: [PATCH] skbuff: Add new tc classify variable Date: Tue, 7 Feb 2012 19:39:08 +0100 Message-ID: <1328639948-25232-1-git-send-email-siwu@hrz.tu-chemnitz.de> To: netdev@vger.kernel.org Return-path: Received: from nick.hrz.tu-chemnitz.de ([134.109.228.11]:37085 "EHLO nick.hrz.tu-chemnitz.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756021Ab2BGSzX (ORCPT ); Tue, 7 Feb 2012 13:55:23 -0500 Received: from p57aa11a5.dip0.t-ipconnect.de ([87.170.17.165] helo=pandem0nium) by nick.hrz.tu-chemnitz.de with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1RupwX-0000XQ-FX for netdev@vger.kernel.org; Tue, 07 Feb 2012 19:39:10 +0100 Received: from dotslash by pandem0nium with local (Exim 4.72) (envelope-from ) id 1Rupwa-0006Zq-7z for netdev@vger.kernel.org; Tue, 07 Feb 2012 19:39:08 +0100 Sender: netdev-owner@vger.kernel.org List-ID: The linux traffic control mechanism has different ways to select the correct class of a qdisc. A common way to do this is to use tc filters that are directly attached to a qdisc. Another approach is to use the iptables classify module. The latter one can reduce the amount of work necessary to process a packet when iptables is already involved in the packet classification. The iptables module can be used in the postrouting chain of the mangle table. # iptables -F -t mangle # iptables -X -t mangle # iptables -t mangle -I POSTROUTING -j CLASSIFY --set-class 1:1337 A simple qdisc with two classes will now route the traffic to 1:1337 # tc qdisc del dev eth0 root # tc qdisc add dev eth0 root handle 1: htb default 1 # tc class add dev eth0 parent 1: classid 1:1 htb rate 15kbit burst 0kbit # tc class add dev eth0 parent 1: classid 1:1337 htb rate 250kbit burst 0kbit # tc -s class show dev eth0 A similar test with an ath9k device will show a complete different behavior. The default class 1:1 will be used and data is sent through. This problem seems to be related to the fact that the shared member variable sk_buff::priority is used to store the tc class id of an outgoing packet. This variable is also used in other places for different purposes. An example is the ieee80211_select_queue function which always overwrites the priority of an outgoing skb. This conflict can be resolved by an additional member variable sk_buff::tc_class that is only used for the traffic control classification. Signed-off-by: Simon Wunderlich Cc: Pablo Neira Ayuso Cc: Patrick McHardy Cc: Jamal Hadi Salim Cc: "David S. Miller" Cc: Johannes Berg Cc: "John W. Linville" Cc: Marek Lindner Cc: Sven Eckelmann Cc: netfilter-devel@vger.kernel.org Cc: netfilter@vger.kernel.org Cc: coreteam@netfilter.org Cc: netdev@vger.kernel.org Cc: linux-wireless@vger.kernel.org --- include/linux/skbuff.h | 2 ++ net/netfilter/xt_CLASSIFY.c | 4 ++-- net/sched/sch_atm.c | 4 ++-- net/sched/sch_cbq.c | 2 +- net/sched/sch_drr.c | 4 ++-- net/sched/sch_dsmark.c | 4 ++-- net/sched/sch_generic.c | 2 +- net/sched/sch_hfsc.c | 4 ++-- net/sched/sch_htb.c | 6 +++--- net/sched/sch_prio.c | 4 ++-- net/sched/sch_sfq.c | 8 ++++---- 11 files changed, 23 insertions(+), 21 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 50db9b0..3ffc301 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -352,6 +352,7 @@ typedef unsigned char *sk_buff_data_t; * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c * @skb_iif: ifindex of device we arrived on * @tc_index: Traffic control index + * @tc_class: Classification index * @tc_verd: traffic control verdict * @rxhash: the packet hash computed on receive * @queue_mapping: Queue mapping for multiqueue devices @@ -439,6 +440,7 @@ struct sk_buff { int skb_iif; #ifdef CONFIG_NET_SCHED + __u32 tc_class; /* traffic control class */ __u16 tc_index; /* traffic control index */ #ifdef CONFIG_NET_CLS_ACT __u16 tc_verd; /* traffic control verdict */ diff --git a/net/netfilter/xt_CLASSIFY.c b/net/netfilter/xt_CLASSIFY.c index af9c4da..9b71957 100644 --- a/net/netfilter/xt_CLASSIFY.c +++ b/net/netfilter/xt_CLASSIFY.c @@ -1,5 +1,5 @@ /* - * This is a module which is used for setting the skb->priority field + * This is a module which is used for setting the skb->tc_class field * of an skb for qdisc classification. */ @@ -33,7 +33,7 @@ classify_tg(struct sk_buff *skb, const struct xt_action_param *par) { const struct xt_classify_target_info *clinfo = par->targinfo; - skb->priority = clinfo->priority; + skb->tc_class = clinfo->priority; return XT_CONTINUE; } diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c index e25e490..003511a 100644 --- a/net/sched/sch_atm.c +++ b/net/sched/sch_atm.c @@ -369,8 +369,8 @@ static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch) pr_debug("atm_tc_enqueue(skb %p,sch %p,[qdisc %p])\n", skb, sch, p); result = TC_POLICE_OK; /* be nice to gcc */ flow = NULL; - if (TC_H_MAJ(skb->priority) != sch->handle || - !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->priority))) { + if (TC_H_MAJ(skb->tc_class) != sch->handle || + !(flow = (struct atm_flow_data *)atm_tc_get(sch, skb->tc_class))) { list_for_each_entry(flow, &p->flows, list) { if (flow->filter_list) { result = tc_classify_compat(skb, diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c index 24d94c0..b1321f9 100644 --- a/net/sched/sch_cbq.c +++ b/net/sched/sch_cbq.c @@ -221,7 +221,7 @@ cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) struct cbq_class *head = &q->link; struct cbq_class **defmap; struct cbq_class *cl = NULL; - u32 prio = skb->priority; + u32 prio = skb->tc_class; struct tcf_result res; /* diff --git a/net/sched/sch_drr.c b/net/sched/sch_drr.c index 6b7fe4a..57b1ca2 100644 --- a/net/sched/sch_drr.c +++ b/net/sched/sch_drr.c @@ -321,8 +321,8 @@ static struct drr_class *drr_classify(struct sk_buff *skb, struct Qdisc *sch, struct tcf_result res; int result; - if (TC_H_MAJ(skb->priority ^ sch->handle) == 0) { - cl = drr_find_class(sch, skb->priority); + if (TC_H_MAJ(skb->tc_class ^ sch->handle) == 0) { + cl = drr_find_class(sch, skb->tc_class); if (cl != NULL) return cl; } diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c index 2c79020..60cfe15 100644 --- a/net/sched/sch_dsmark.c +++ b/net/sched/sch_dsmark.c @@ -224,8 +224,8 @@ static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch) } } - if (TC_H_MAJ(skb->priority) == sch->handle) - skb->tc_index = TC_H_MIN(skb->priority); + if (TC_H_MAJ(skb->tc_class) == sch->handle) + skb->tc_index = TC_H_MIN(skb->tc_class); else { struct tcf_result res; int result = tc_classify(skb, p->filter_list, &res); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 67fc573..c14779a 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -449,7 +449,7 @@ static inline struct sk_buff_head *band2list(struct pfifo_fast_priv *priv, static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc) { if (skb_queue_len(&qdisc->q) < qdisc_dev(qdisc)->tx_queue_len) { - int band = prio2band[skb->priority & TC_PRIO_MAX]; + int band = prio2band[skb->tc_class & TC_PRIO_MAX]; struct pfifo_fast_priv *priv = qdisc_priv(qdisc); struct sk_buff_head *list = band2list(priv, band); diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c index 9bdca2e..2fcc6ef 100644 --- a/net/sched/sch_hfsc.c +++ b/net/sched/sch_hfsc.c @@ -1154,8 +1154,8 @@ hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) struct tcf_proto *tcf; int result; - if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 && - (cl = hfsc_find_class(skb->priority, sch)) != NULL) + if (TC_H_MAJ(skb->tc_class ^ sch->handle) == 0 && + (cl = hfsc_find_class(skb->tc_class, sch)) != NULL) if (cl->level == 0) return cl; diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c index 29b942c..ef8dd42 100644 --- a/net/sched/sch_htb.c +++ b/net/sched/sch_htb.c @@ -197,13 +197,13 @@ static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch, struct tcf_proto *tcf; int result; - /* allow to select class by setting skb->priority to valid classid; + /* allow to select class by setting skb->tc_class to valid classid; * note that nfmark can be used too by attaching filter fw with no * rules in it */ - if (skb->priority == sch->handle) + if (skb->tc_class == sch->handle) return HTB_DIRECT; /* X:0 (direct flow) selected */ - cl = htb_find(skb->priority, sch); + cl = htb_find(skb->tc_class, sch); if (cl && cl->level == 0) return cl; diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c index b5d56a2..f53a5b99 100644 --- a/net/sched/sch_prio.c +++ b/net/sched/sch_prio.c @@ -34,12 +34,12 @@ static struct Qdisc * prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) { struct prio_sched_data *q = qdisc_priv(sch); - u32 band = skb->priority; + u32 band = skb->tc_class; struct tcf_result res; int err; *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; - if (TC_H_MAJ(skb->priority) != sch->handle) { + if (TC_H_MAJ(skb->tc_class) != sch->handle) { err = tc_classify(skb, q->filter_list, &res); #ifdef CONFIG_NET_CLS_ACT switch (err) { diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 67494ae..79bc0ac 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -190,10 +190,10 @@ static unsigned int sfq_classify(struct sk_buff *skb, struct Qdisc *sch, struct tcf_result res; int result; - if (TC_H_MAJ(skb->priority) == sch->handle && - TC_H_MIN(skb->priority) > 0 && - TC_H_MIN(skb->priority) <= q->divisor) - return TC_H_MIN(skb->priority); + if (TC_H_MAJ(skb->tc_class) == sch->handle && + TC_H_MIN(skb->tc_class) > 0 && + TC_H_MIN(skb->tc_class) <= q->divisor) + return TC_H_MIN(skb->tc_class); if (!q->filter_list) { skb_flow_dissect(skb, &sfq_skb_cb(skb)->keys); -- 1.7.8.3